Thanks Kovid. I have just reset the dialogs; never noticed I disabled them, but my Calibre installations are so ancient…
Do you still convert to RTF, BetterRed? DOCX conversion is so more powerful that I only convert with it.
Sometimes I still merge all HTML, change the header and the paths to stylesheet and images, then open with Libroffice, but it became nearly useless.
I have only two little issues with DOCX conversion:
* Character styles may be a little tricky to handle if you want to modify with a word processor, so I often open-save the DOCX with a word processor like Atlantis which does not know character styles and converts to direct formatting. (The names of these styles begin with numbers, so that I also have to change them when making ebooks with Amanuensis

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* When a paragraph contains mostly italics, an italic paragraph style is created and all the text is in italics (But maybe this has been improved…)